Mix all the meatball ingredients together. Form meatballs, each 1/2 inch in diameter. Mix harissa, caraway, garlic and tomato paste together and put in a large pan. Mix flour briskly with 3 cups of water into a smooth paste and put into a pan. Simmer over low heat adding 1 cup water every 5 minutes. Stir slowly and continuously with a wooden spoon. Add meatballs, salt and mint. Continue to simmer over low heat for another 10 minutes. Serve.